Clean up CONTRIBUTING.md

Author: mflendrich

CONTRIBUTING.md

@@ -1,14 +1,5 @@
 # Contributing to Scylla Operator
 
-## Prerequisites
-
-To develop Scylla Operator, ensure your environment has the following items configured:
-
-1. [Go](https://golang.org/dl)
-   * Check `go.mod` for minimal version requirement.
-2. Git client
-3. GitHub account
-
 ## Initial Setup
 
 ### Fork the repository
@@ -67,8 +58,8 @@ Imagine writing to yourself in 12 months when you've forgotten everything about
 If the change fixes an issue, then write Fixes #1234 in the PR description.
 
 Here is an example of a good commit message and PR title/description:
-```
 
+```
 Add new XYZ field to ScyllaCluster CRD.
 
 The new field allows for configuration of ZYX feature of ScyllaDB.